The present invention relates to a route search system, route search terminal, and route search method for searching an optimum route in view of environmental loads.
Recent route search systems are fabricated taking various factors in consideration. These factors include conventional ones such as a minimum distance or a minimum time of travel from a present location to a destination, and a degree of priority to expressways. In addition, environmental factors such as the roadside environment are also included in these factors.
A route search system or route search terminal designed in consideration of the environment calculates an effect given by a relevant vehicle to the environment based on traffic information collected in the past and traffic information collected in real-time to find a route in which the effect is minimal.
Such route search systems or devices designed in consideration of the environment are described for example in Japanese Laid-Open Patent Publication No. 2002-230685 (Patent Document 1) and No. 2005-030823 (Patent Document 2).
Patent Document 1 describes a roadside environment monitoring system and method capable of measuring the roadside environment possibly deteriorated by travel of vehicles by employing an ITS (Intelligent Transport System) to measure the roadside environment by means of various sensors and to detect traveling vehicles. The roadside environment monitoring system and method are also capable of preventing the environment from being worsened by imposing restrictions or charging when deterioration in the environment has exceeded a certain value.
Patent Document 2 describes a route search apparatus which searches a route from a starting point to a destination by calculating an amount of greenhouse gas discharged by a relevant vehicle during a travel from the starting point to the destination to find a route in which the discharged greenhouse gas amount is minimal. Patent Document 2 also describes a route search apparatus for searching a route by providing a relevant vehicle with a sensor to measure a greenhouse gas amount and finding a route in which a greenhouse gas amount possibly discharged by the vehicle is minimal on the basis of the actually measured greenhouse gas amount.
Traffic information systems are also generally known, which transmit traffic information such as travel time or traffic jam information for each road (link).